Adaptive footwear

ABSTRACT

A shoe includes a flexible, bistable heel flap to facilitate access to a foot-receiving cavity of the shoe. The flexible, bistable heel flap moves between an open stable position and an upright position suitable for use. At the open stable position, the flexible, bistable heel flap bends away from the foot-receiving cavity of the shoe. A fastener may secure the flexible, bistable heel flap in the upright position suitable for use.

FIELD OF THE INVENTION

The present application relates to articles of footwear and, more specifically, relates to adaptive articles of footwear for Ankle-Foot Orthosis (“AFO”) users.

BACKGROUND

AFO users generally have difficulty wearing traditional articles of footwear, which makes walking difficult and cumbersome. There is a need for an adaptive article of footwear (“adaptive shoe”) that affords AFO users ease of use and access. Current articles of footwear ineffectually accommodate AFO users and do not consider the bulk of the user's orthosis. When the user wears an AFO within a current article of footwear, the bulk of the AFO lends to fit, sizing, and comfort issues.

Because current articles of footwear ineffectually accommodate AFO users, a new article is necessary in the field.

SUMMARY

Aspects of the present disclosure are directed towards a shoe comprising a sole extending in length from a toe portion to a heel portion. The shoe comprises a vamp coupled to the sole. The vamp forms a forward, foot-receiving cavity and includes a vamp upper portion and a toe box. The shoe further comprises anchoring loops coupled to the vamp and a flexible, bistable heel flap coupled to the heel portion of the sole. The flexible, bistable heel flap comprises an upper edge, a fastener below the upper edge, and a bending region below the fastener. The upper edge of the flexible, bistable heel flap may bend away from the forward foot-receiving cavity at the bending region to a stable open position. Further, the fastener may couple to the anchoring loops to secure the flexible, bistable heel flap in a stable upright position. When the shoe is in the stable upright position, the shoe forms a medial slot and a lateral slot between a respective medial side and lateral side of the vamp upper portion and the flexible, bistable heel flap.

Additional aspects of the present disclosure are directed towards a shoe comprising a sole extending in length from a toe portion to a heel portion and in width from a medial side to a lateral side. The shoe further comprises a vamp upper portion attached to the sole. The vamp upper portion comprises a toe box, a medial side, and a lateral side. The medial side and lateral side extend from the toe box and terminate in medial and lateral edges to form a forward foot-receiving cavity. The shoe further comprises a flexible, bistable heel flap attached to the heel portion of the sole. The flexible, bistable heel flap comprises an inner surface, an outer surface, an upper edge, a medial edge, a lateral edge and a bottom edge fastened to the heel portion of the sole. The upper edge of the flexible, bistable heel flap is bendable away from the forward foot-receiving cavity between a stable open position and a stable upright position about a bending region of the flexible, bistable heel flap. The bending region is located between the upper edge and the bottom edge. The shoe further comprises a fastening strap. The fastening strap secures the flexible, bistable heel flap relative to the vamp upper portion. The fastening strap comprises a middle portion anchored to the outer surface of the flexible, bistable heel flap, a first free end and a second free end. The first free end of the fastening strap extends from the medial edge of the flexible, bistable heel flap for connecting to the medial side of the vamp upper portion. The second free end extends from the lateral edge of the flexible, bistable heel flap for connecting the lateral side of the vamp upper portion. Thus, the middle portion stiffens the bending region of the flexible, bistable heel flap to promote bending about the bending region of the flexible, bistable heel flap.

Additional aspects of the present disclosure are directed towards a shoe comprising a sole extending in length from a toe portion to a heel portion and in width from a medial side to a lateral side. The shoe further comprises a vamp upper portion attached to the sole. The vamp upper portion comprises a toe box, a medial side, and a lateral side. The medial side and lateral side extend from the toe box and terminate in respective medial and lateral edges to form a forward foot-receiving cavity. The shoe further comprises a flexible, bistable heel flap attached to the heel portion of the sole. The flexible, bistable heel flap comprises an inner surface, an outer surface, an upper edge, a medial edge, a lateral edge and a bottom edge fastened to the heel portion of the sole. The upper edge of the flexible, bistable heel flap is bendable away from the forward foot-receiving cavity between a stable open position and a stable upright position about a bending region of the flexible, bistable heel flap. The bending region is located between the upper edge and the bottom edge. The shoe further comprises a moveable finger tab on the inside surface of the flexible, bistable heel flap.

Numerous other advantages and features of the present disclosure will become readily apparent from the following detailed description of the disclosure and the embodiments thereof, from the claims and from the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The present disclosure is illustrated by way of example and not limited in the accompanying figures in which like reference numerals indicate similar elements, in which:

FIG. 1A is an isometric view of an adaptive shoe in an open position, according to an embodiment of the present disclosure;

FIG. 1B is a detailed view of a fastening loop of the adaptive shoe shown in FIG. 1A;

FIG. 2A is an isometric view of the adaptive shoe of FIG. 1A in a foot-engaging position, according to an embodiment of the present disclosure;

FIG. 2B is a detailed view of a fastening loop of the adaptive shoe as shown in FIG. 2A

FIG. 3 is an anterior view of the adaptive shoe of FIG. 1A showing the heel flap in a bent, open position;

FIG. 4 is an anterior view of the adaptive shoe of FIG. 2A showing the heel flap in an upright position;

FIG. 5A is a detailed isometric view of an end portion of the shoe of FIG. 1A showing a medial slot and a lateral slot in an expanded position; and

FIG. 5B shows the medial and lateral slots of FIG. 5A in a contracted, foot-engaging position.

DETAILED DESCRIPTION

An AFO is a podiatric device often used to control instabilities in a lower limb of a user to maintain alignment, control motion, and support muscular imbalance. Such devices often help children and adults suffering from neurological or orthopedic conditions that affect their joints, movement, and posture. While many AFO's exist in the art, AFO's generally comprise a custom-fabricated structure enclosing at least a portion of the user's foot and ankle. This structure ensures that the AFO user's foot is appropriately positioned to achieve its desired benefit.

An AFO may be worn by itself. However, AFO users often wear both the AFO and traditional articles of footwear tandemly. While a special article of footwear is not needed to accommodate the orthosis, the bulk of the AFO inserted into traditional articles of footwear often requires the user to purchase larger articles of footwear or remove any insole to create additional room.

To address these issues, an exemplary adaptive shoe 100 provides the use of a flexible, bistable heel flap 305, as shown in FIGS. 1A and 2A. The flexible, bistable heel flap 305 serves a dual purpose. First, the flexible, bistable heel flap 305 facilitates insertion of a user's foot in the adaptive shoe 100. Second, the flexible, bistable heel flap 305 allows adjustments of the adaptive shoe 100 to fit the user's foot. In doing so, the exemplary embodiment provides an easy way for an AFO user to independently adjust the adaptive shoe 100 while ensuring proper size, size, and comfort. However, the exemplary embodiment of the adaptive shoe 100 is not limited to use for an AFO user and may be used by any user of footwear.

Referring now to FIGS. 1A-5B, FIGS. 1A, 3 and 5A show an adaptive shoe 100 in an open position, with the heel flap 305 bent backwards to facilitate insertion of a foot. FIGS. 2A, 4 and 5B show the adaptive shoe 100 in an engaged position, with the heel flap in a substantially upright, unbent position after insertion of a foot so that the heel flap covers a user's heel. FIGS. 1B and 2B show the process of fastening a fastening strap to secure the shoe 100 in an engaged position.

The illustrative adaptive shoe 100 comprises a sole 105 forming the bottom of the adaptive shoe 100 and an upper coupled to the sole 105. The upper includes a vamp 205 and a flexible, bistable heel flap 305 that may be moved between the bent and upright positions. A connecting portion 110 connects the bottom of the vamp 205 with the bottom of the flexible, bistable heel flap 305. The vamp 205, connecting portion 110, and flexible, bistable heel flap 305 may be integrally formed to form a continuous upper, as shown, or separate components joined together. The flexible, bistable heel flap 305 is stable in either the bent position or the upright position, i.e., once it is in that position, it remains substantially in that position unless moved by force.

The illustrative sole 105 extends in length from a toe portion 115 to a heel portion 120, and in width from a medial side to a lateral side. The sole 105 may comprise a length sufficient to accommodate at least the length of an AFO user's foot. In the representative embodiment and without limitation, the sole 105 comprises natural rubber. Other alternative materials that could comprise the sole 105 include, for example and without limitations, foam, thermoplastics, polyurethane, polyvinyl chloride (PVC) compounds, or combinations thereof, all of which are considered equivalent and within the scope of the disclosure.

The vamp 205 includes a toe box 210 at a front end. The vamp extends from the toe box 210 towards the heel portion 120 and includes a medial side, a lateral side and a tongue 215, but the disclosure is not so limited. The medial and lateral portions of the vamp 205 terminate at respective medial and lateral downward-angled edges 220, 225. As described below, the vamp 205 further includes anchoring loops 230 on the medial portion and the lateral portion to selectively secure the flexible, bistable heel flap 305 relative to the vamp 205. The illustrative upper portion of the vamp 205 extends proximally from the toe box 210, and at a length sufficient to cover at least the forefront of the sole 105.

Together, the sole 105, the upper, medial, and lateral portion of the vamp 205, and the toe box 210 form a forward foot-receiving cavity for the user's foot.

The illustrative vamp 205 comprises textiles. Other alternative materials that could comprise vamp 205 include, for example and without limitations, leathers, synthetics, rubber, foam, plastic, and combinations thereof, all of which are considered equivalent and within the scope of the disclosure.

The illustrative medial and lateral portions of the vamp 205 include anchoring loops 230, shown in detail in FIGS. 1B and 2B. The illustrative anchoring loops 230 have a substantially triangular shape and are placed at a position near and below the respective medial or lateral downward-angled edge 220, 225 of the vamp 205. The anchoring loops 230 may be any shape (e.g., circular, rectangular, etc.). Further, the anchoring loops 230 may comprise materials including, and without limitation, plastics, synthetics, textiles, and combinations thereof, all of which are considered equivalent and within the scope of disclosure. The anchoring loops may be coupled to the vamp 205 through any suitable means.

Opposite the forward foot-receiving cavity at the back of the shoe 100, the heel of the upper comprises a flexible, bistable heel flap 305 that may move between a bent position, shown in FIGS. 1A, 3, 5A and an upright position, shown in FIGS. 2A, 4 and 5B. In the bent position, the flexible, bistable heel flap 305 is bent back away from the forward foot-receiving cavity to open the shoe and facilitate access to the forward foot-receiving cavity. In the upright position, the flexible, bistable heel flap 305 is substantially straight to enclose the heel of the user's foot and allow the user to wear the shoe. The flexible, bistable heel flap 305 further includes a finger tab 310 as described below. A fastener 315 may be used to connect and position the flexible, bistable heel flap 305 relative to the vamp 205 portion. Further, the flexible, bistable heel flap 305 may extend from the heel portion 120 of the sole. The illustrative flexible, bistable heel flap 305 extends from an inner surface of the heel portion 120 of the sole 105.

The illustrative bistable heel flap 305 includes medial and lateral edges 320, 325, as best shown in FIG. 3 . In an upright position, the respective medial and lateral edges 320, 325 of the flexible, bistable heel flap 305 oppose, and are spaced from, the medial and lateral portion of vamp 205 to form a respective medial slot 405 and lateral slot 410 separating the flap 305 from the vamp 205 when the shoe is in the engaged position. The illustrative flexible, bistable heel flap 305 tapers from a top edge 330 to a bottom 335, or at least to a bending region 340 so that the respective medial and lateral slots 405, 410 angle downwards towards the heel of the adaptive shoe 100 when the flap 305 is upright to place the shoe in a foot-engaging position, as shown in FIGS. 2A and 5B. The bottom 335 of the flap 305 may be fastened within the inside of the sole 105. The slots 405, 410 extend from the top edges of the flexible, bistable heel flap 305 and vamp portion almost to the sole 105. The upper includes connecting portions 110, which may be integral with the flexible, bistable heel flap 305 and—or vamp 205 that connect the bottom of the vamp 210 and the flexible, bistable heel flap 305. The connecting portions 110 have top curved edges to promote bending of the heel flap 305. Alternatively, the respective medial and lateral slots 405, 410 extend to the sole 105, omitting the connecting portions 110.

The illustrative flexible, bistable heel flap 305, and the fastener 315 comprise textiles to allow flexibility. Other alternative materials that could comprise the flexible, bistable heel flap 305, and fastener 315 include, for example and without limitation, leathers, synthetics, rubber, foams, plastics, and combinations thereof, all of which are considered equivalent and within the scope of the disclosure. In one embodiment, the outer surface of the flexible, bistable heel flap 305 may include an additional strengthening layer form of leather, rubber, or another suitable material.

The illustrative fastener 315 comprises a fastening strap. The illustrative fastening strap 315 comprises textiles. Other alternative material that could comprise the fastening strap 315, include, for example and without limitations, leathers, synthetics, rubber, foam, plastic, and combinations thereof, all of which are considered equivalent and within the scope of the disclosure. The illustrative fastening strap 315 comprises a middle portion, a first free end 345 extending from the medial edge 320 of the flexible, bistable heel flap 305 and a second free end 350 (shown in FIG. 3 ) extending from the lateral edge 325 of the flexible, bistable heel flap 305. The free ends 345, 350 bridge the slots 405, 410 and connect to the anchoring loops 230 to connect the flexible, bistable heel flap 305 to the vamp. The middle portion of fastening strap 315 extends laterally between the upper edge 330 of the flexible, bistable heel flap 305 and the bending region 340 of the flexible, bistable heel flap 305, to promote bending of the flexible, bistable heel flap 305, as shown in FIG. 4 .

Although FIGS. 1A-4 depict a fastening strap 315 having a substantially rectangular shape, the fastening strap 315 may be any shape so long as the first free end 345 and the second free end 350 compatibly couple to the anchoring loops 230. A person of ordinary skill in the art should interpret compatibly couple to include, without limitation, a slotable connection and-or at least an appropriate connection between the shape of the anchoring loops 230 and the fastening strap 315.

Prior to inserting their foot into the adaptive shoe 100, the AFO user may achieve the open position by bending away the flexible, bistable heel flap 305 about the bending region 340 to a stable, substantially horizontal position, as shown in FIGS. 1A, 3 and 5A. However, a person of ordinary skill in the art should interpret bending away to include, without limitation, bending the flexible, bistable heel flap 305 to any degree beyond a vertical position.

The open position of the adaptive shoe 100 facilitates insertion of the user's foot into the adaptive shoe 100. Specifically, when the adaptive shoe 100 is in the open position, the flexible, bistable heel flap 305 may bend away from the forward foot-receiving cavity to accommodate the bulk of the AFO, expanding the entrance of the foot-receiving cavity and afford adjustability during foot insertion.

Once a user inserts their foot into the adaptive shoe 100, the user may manipulate features of the adaptive shoe 100 to secure the user's foot within the shoe.

The illustrative adaptive shoe 100 achieves the engaged position shown in FIGS. 2A, 4 and 5B by pushing the flexible, bistable heel flap 305 towards the toe box. The finger tab 310 may be used to facilitate transition of the flap 305. Then, the user may anchor the first free end 345 and the second free end 350 of the fastening strap 315 to a corresponding anchoring loop 230 such that the flexible, bistable heel flap 305 remains a substantially fixed distance from the vamp 205. Advantageously, in the engaged position the flexible, bistable heel flap 305 cannot bend away from the forward foot-receiving cavity of the adaptive shoe 100.

When the adaptive shoe 100 is in the engaged position, the medial and lateral slots 405, 410 separate the vamp 205 and the flexible, bistable heel flap 305. In any embodiment, the width of the medial and lateral slots 405, 410 between vamp 205 and bistable heel flap 305 needs to only be at such a distance that the heel portion 120 of the adaptive shoe 100 fits comfortably over the distal end of a user's heel. In embodiments, a person of ordinary skill in the art should interpret comfortably to mean a fit comprising, for example and without limitation to, friction.

The illustrative means for anchoring the fastening strap 315 to the anchoring loops 230 includes, without limitation, looping. Specifically, the first free end 345 and the second free end 350 of the fastening strap 315 may include a hook strip portion 355 and a loop strip portion 360. as shown in FIG. 1B. After inserting the free end 350 of the fastening strap through a corresponding anchoring loop 230, as shown in FIG. 1B, the hook strip portion 355 of the fastening strap 315 may engage the loop strip portion 360 to locate the flexible, bistable heel flap 305 at a position according to the user's preference, as shown in FIG. 2B.

Looping the hook strip portion 355 through the anchoring loops 230 and coupling the hook strip portion 355 to the loop strip portion 360 of the first free end 345 and second free end 350 secures the bistable heel flap 305 and affords adaptability of the adaptive shoe 100 based on the size of the AFO user's foot and the bulk of the AFO.

Further, a person of ordinary skill in the art should interpret the fastening strap 315 to include a length sufficient to engage anchoring loops 230 for coupling. The exact length of fastening strap 315 may vary inasmuch as the final length in any embodiment is long enough to ensure appropriate coupling between the first free end and second free end of fastening strap 315 and anchoring loops 230.

In the engaged, upright position, the flexible, bistable heel flap 305 may bend to accommodate the bulk of the AFO, if used and afford adjustability during foot insertion. However, in the representative embodiment and without limitations, in the engaged, upright position, the flexible, bistable heel flap 305 may angle slightly towards the toe portion of the adaptive shoe 100.

The illustrative bending region 340 is formed between the fastener 315 and the fixed bottom of the flexible, bistable heel flap 305. The fastener 315 may stiffen the portion of the flexible, bistable heel flap 305 above the bending region 340 to promote bending.

As shown in FIG. 3 the flexible, bistable heel flap 305 comprises an inner surface 365. The illustrative inner surface 365 comprises textiles. Other alternative materials that could comprise inner surface 365 include, for example and without limitations, leathers, synthetics, rubber, foams, plastics, and combinations thereof, all of which are considered equivalent and within the scope of the disclosure.

The illustrative flexible, bistable heel flap 305 includes a finger tab 310, which couples to the inner surface 365. Advantageously, the position of the finger tab 310 on the inner surface 365 affords the user the ability to manually adjust the orientation or bend the flexible, bistable heel flap 305. The illustrative finger tab 310 comprises textiles. Other alternative materials that could comprise finger tab 310 include, for example and without limitations, leathers, synthetics, rubber, foams, plastics, and combinations thereof, all of which are considered equivalent and within the scope of the disclosure.

As shown in FIG. 3 , the illustrative finger tab 310 is anchored to the inner surface 365 by a first overlay 370 stitched to the inner surface 365 and a second overlay 375 stitched to inner surface 365. The overlays 370, 375 anchor the free ends of the finger tab 310 forming a loop sufficient for receiving a user's finger. Other alternative materials that could comprise anchoring include, for example and without limitation, adhesives, and combinations thereof, all of which are considered equivalent and within the scope of the disclosure.

The first overlay 370 and second overlay 375 may comprise textiles. Other alternative materials that could comprise the first overlay 370 and the second overlay 375 include, for example and without limitations, leathers, synthetics, rubber, foams, plastics, and combinations thereof, all of which are considered equivalent and within the scope of the disclosure.

The illustrative flexible, bistable heel flap 305 extends from within the heel portion 120 of the sole 105.

Referring to FIGS. 5A and 5B, in the open position, the medial slot 405 extends between at least a medial side of the vamp 205 and between the flexible, bistable heel flap 305. Further the lateral slot 410 extends between a lateral side of the vamp 205 and between the flexible, bistable heel flap 305.

The illustrative medial slot 405 comprises a substantially curved bottom portion. The illustrative lateral slot 410 comprises a substantially curved bottom portion to facilitate bending of the flexible, bistable heel flap 305.

In exemplary embodiments, the bottom edges of the medial slot 405 and lateral slot 410 extend in height above the sole to between 0 cm and about 2 cm and in length of sole 105. The illustrative slots 405, 410 have a length between 3 cm and about 5 cm, depending on the height of the shoe 100.

In the open position of FIG. 5A, the medial slot 405 and lateral slot 410 widen from the sole to the top of the slot, forming a first width 415. The first width 415 is at least sufficient for the medial slot 405 and lateral slot 410 to surround at least the length of the AFO user's ankle during foot insertion. The width 415 has a range of width extending at least between 3 cm to 10 cm.

Once foot insertion occurs, the shoe user achieves the engaged position by pulling the finger tab 310 up and towards the toe, bringing the heel flap 305 into a substantially upright position. Further, the shoe user achieves the engaged position by looping the first free end 345 through an anchoring loop 230 and coupling, in the anterior direction, the first free end 345 to the fastening strap 315.

In the engaged position, the medial slot 405 and lateral slot 410 comprise a second, smaller width 420, which may be consistent from the top to the bottom curved portion, or may taper or widen from top to bottom. The slots 405, 410 can be adjusted in the engaged position using the fastening strap 315 to achieve an optimal position of the flexible, bistable heel flap 305, thereby adjusting the width and configuration of the slots 405, 410.

The invention is not limited to the illustrative embodiments and encompasses variations and alterations of these embodiments.

The present invention is amenable to many different embodiments. The drawings and description will detail a specific embodiment, with the understanding that the present disclosure is to be considered an example of the principles of the invention, but not intended to limit the invention to only the embodiment illustrated. The embodiments thereof, are only an illustration of the invention and not meant to be restrictive. This embodiment is also not limited in its applied construction or to the arrangements of components set forth in the specification or illustrations. The methods consistent with this invention are capable of other embodiments and being used in various ways. It should be understood that the terminology and the language used in this patent are not meant to be limiting and are for the purposes for description. In the description herein, specific details are provided in order to create a thorough understanding of the embodiments of the present invention. One skilled in the relevant art will recognize that the embodiment of the invention can be practiced without one or more of the specific details or with other apparati, assemblies, components, materials, parts etc. Well known structures, materials, or operations are not specifically shown or described in detail to avoid blurring the present invention. Furthermore, Figures that are not drawn are not meant to limit the present invention. 

1. A shoe, comprising: a sole extending in length from a toe portion to a heel portion; a vamp coupled to the sole and forming a forward, foot-receiving cavity, wherein the vamp comprises: a vamp upper portion; and a toe box; a plurality of anchoring loops coupled to the vamp; a flexible, bistable heel flap coupled to the heel portion, the flexible, bistable heel flap comprising: an upper edge; a fastener below the upper edge; and a bending region below the fastener, wherein the upper edge of the flexible, bistable heel flap bends away from the forward, foot-receiving cavity at the bending region to a stable open position, and wherein the fastener couples to the plurality of anchoring loops to secure the flexible, bistable heel flap in a stable upright position; a medial slot between a medial side of the vamp upper portion and the flexible, bistable heel flap when the flexible, bistable heel flap is in the stable upright position; and a lateral slot between a lateral side of the vamp upper portion and the flexible, bistable heel flap when the flexible, bistable heel flap is in the stable upright position.
 2. The shoe of claim 1, wherein the fastener comprises a fastening strap, the fastening strap comprising: a middle portion, wherein the middle portion couples to an outside surface of the flexible, bistable heel flap; a first free end extending from a medial edge of the flexible, bistable heel flap; and a second free end extending from a lateral edge of the flexible, bistable heel flap, wherein the first free end and the second free end each loop an anchoring loop to secure the flexible, bistable heel flap in the stable upright position.
 3. The shoe of claim 2, wherein the first free end and the second free end each include a hook strip portion and a loop strip portion.
 4. The shoe of claim 1, wherein the vamp upper portion further comprises: a medial portion terminating at a downward-angled edge; and a lateral portion terminating at a downward-angled edge.
 5. The shoe of claim 4, wherein a first anchoring loop of the plurality of anchoring loops couples to the vamp at a position below the medial downward-angled edge, and wherein a second anchoring loop of the plurality of anchoring loops couples to the vamp at a position below the lateral downward-angled edge.
 6. The shoe of claim 4, further comprising: a first upper connecting portion that couples to the sole between the vamp upper portion and the flexible, bistable heel flap for connecting a bottom of the medial downward-angled edge to a bottom of the medial edge of the bistable heel flap to form a bottom of the medial slot; and a second upper connecting portion that couples to the sole between the vamp upper portion and the flexible, bistable heel flap for connecting a bottom of the lateral downward-angled edge to a bottom of the lateral edge of the bistable heel flap to form a bottom of the lateral slot.
 7. The shoe of claim 6, wherein the first upper connecting portion and the second upper connecting portion have curved upper edges.
 8. The shoe of claim 6, wherein the first connecting upper portion and second upper connecting portion have top edges that are between about 0 cm and about 2 cm above the sole, so that the medial slot and lateral slot extend almost to the sole.
 9. The shoe of claim 6, wherein the vamp, the first connecting upper portion, the first connecting upper portion, and the flexible, bistable heel flap form a continuous upper.
 10. The shoe of claim 1, wherein the flexible, bistable heel flap further comprises: an inner surface; and a bottom edge coupling to the sole within the heel portion, wherein the flexible, bistable heel tapers from the upper edge to the bottom edge to form angled medial and lateral edges.
 11. The shoe of claim 10, further comprising a finger tab coupled to the inner surface of the flexible, bistable heel flap comprising: a first end; a second end; a first overlay stitched to the inner surface of the flexible, bistable heel flap for anchoring the first end; and a second overlay stitched to the inner surface for anchoring the second end.
 12. The shoe of claim 11, wherein pulling the finger tab helps secure the flexible, bistable heel flap in the stable upright position.
 13. The shoe of claim 1, wherein the flexible, bistable heel flap is substantially horizontal in the stable open position.
 14. The shoe of claim 1, wherein the flexible, bistable heel flat angles slightly towards the toe portion of the shoe in the stable upright position to enclose a heel of a user's foot.
 15. A shoe, comprising: a sole extending in length from a toe portion to a heel portion and in width from a medial side to a lateral side; a vamp upper portion attached to the sole, the vamp upper portion comprising a toe box, a medial side extending from the toe box and terminating in a medial edge and a lateral side extending from the toe box and terminating in a lateral edge to form a forward foot-receiving cavity; a flexible, bistable heel flap attached to the heel portion of the sole, the flexible, bistable heel flap comprising an inner surface, an outer surface, an upper edge, a medial edge, a lateral edge and a bottom edge fastened to the heel portion of the sole, the upper edge of the flexible, bistable heel flap bendable away from the forward foot-receiving cavity between a stable open position and a stable upright position about a bending region of the flexible, bistable heel flap located between the upper edge and the bottom edge; and a fastening strap securing the flexible, bistable heel flap relative to the vamp upper portion, the fastening strap comprising a middle portion anchored to the outer surface of the flexible, bistable heel flap, a first free end extending from the medial edge of the flexible, bistable heel flap for connecting to the medial side of the vamp upper portion and a second free end extending from the lateral edge of the flexible, bistable heel flap for connecting to the lateral side of the vamp upper portion, such that the middle portion stiffens the bending region of the flexible, bistable heel flap to promote bending about the bending region of the flexible, bistable heel flap.
 16. The shoe of claim 15, wherein the vamp medial edge, vamp lateral edge, flexible, bistable heel flap medial edge and flexible, bistable heel flap lateral edge are angled and parallel to each other to form an angled medial slot and an angled lateral slot between the vamp and flexible, bistable heel flap.
 17. The shoe of claim 15, wherein the vamp medial portion includes a first anchoring loop for receiving the first free end of the fastening strap and the vamp lateral portion includes a second anchoring loop for receiving the second free end of the fastening strap to secure the flexible, bistable heel flap in the stable upright position.
 18. A shoe, comprising: a sole extending in length from a toe portion to a heel portion and in width from a medial side to a lateral side; a vamp upper portion attached to the sole, the vamp upper portion comprising a toe box, a medial side extending from the toe box and terminating in a medial edge and a lateral side extending from the toe box and terminating in a lateral edge to form a forward foot-receiving cavity; a flexible, bistable heel flap attached to the heel portion of the sole, the flexible, bistable heel flap comprising an inner surface, an outer surface, an upper edge, a medial edge, a lateral edge and a bottom edge fastened to the heel portion of the sole, the upper edge of the flexible, bistable heel flap bendable away from the forward foot-receiving cavity between a stable open position and a stable upright position about a bending region located between the upper edge and the bottom edge; a finger tab on the inside surface of the flexible, bistable heel flap.
 19. The shoe of claim 18, wherein the finger tab is anchored at a first end by a first overlay stitched to the inner surface and at a second end by a second overlay stitched to the inner surface.
 20. The shoe of claim 18, wherein the finger tab is located between the upper edge of the flexible, bistable heel flap and the bending region. 